vfs: make the string hashes salt the hash

We always mixed in the parent pointer into the dentry name hash, but we
did it late at lookup time.  It turns out that we can simplify that
lookup-time action by salting the hash with the parent pointer early
instead of late.

A few other users of our string hashes also wanted to mix in their own
pointers into the hash, and those are updated to use the same mechanism.

Hash users that don't have any particular initial salt can just use the
NULL pointer as a no-salt.

Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: George Spelvin <linux@sciencehorizons.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index a283f9e796c1..23e5808a0970 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -413,7 +413,7 @@ void smk_insert_entry(struct smack_known *skp)
         unsigned int hash;
         struct hlist_head *head;
 
-        hash = full_name_hash(skp->smk_known, strlen(skp->smk_known));
+        hash = full_name_hash(NULL, skp->smk_known, strlen(skp->smk_known));
         head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)];
 
         hlist_add_head_rcu(&skp->smk_hashed, head);
@@ -433,7 +433,7 @@ struct smack_known *smk_find_entry(const char *string)
         struct hlist_head *head;
         struct smack_known *skp;
 
-        hash = full_name_hash(string, strlen(string));
+        hash = full_name_hash(NULL, string, strlen(string));
         head = &smack_known_hash[hash & (SMACK_HASH_SLOTS - 1)];
 
         hlist_for_each_entry_rcu(skp, head, smk_hashed)